The Islamic State (IS) militant group say its Yemeni affiliate carried out a car-bomb attack at a funeral attended by Shia Houthi rebels in the capital.
Nearly 30 people were injured, Reuters news agency said. An unconfirmed report says many people were killed.
The blast happened near a military hospital in Sanaa on Monday night.
It is the latest attack by IS against Houthis in Yemen, where the Sunni extremist group declared its presence in November.
Houthis have been fighting forces loyal to Yemen’s exiled President Abdrabbuh Mansour Hadi for several months.
A Saudi-led coalition launched air strikes in March, claiming to target Houthi positions. The strikes have had a devastating impact on civilians.
In a separate development on Monday, the rebels said in a statement that they had launched a Scud missile across the border at a Saudi military base. They said the missile was fired “in response to the crimes of the brutal Saudi aggression”.
If confirmed, it would be the second such attack since fighting began.
A Scud missile fired from Yemen earlier this month was shot down by Saudi Arabia before it could reach its target.
Monday’s car-bomb attack appears to have targeted a funeral attended by two brothers who are leaders in the Shia Houthi rebel movement.
The number of casualties is unclear. AFP news agency reports 28 dead, including eight women.
An earlier report by Reuters news agency said 28 people were injured in the blast, including 12 women.
IS posted a statement online saying its Yemeni affiliate was behind the attack. The group has carried out a number of attacks in the capital in recent weeks.
Separately on Monday, UN Secretary General Ban Ki-moon called for a full investigation after a Saudi-led coalition air strike hit a UN compound in the southern city of Aden on Sunday, injuring one guard.
Yemen has been in turmoil since Houthi rebels overran Sanaa last September, forcing President Mansour Abdrabbuh Hadi to flee.
Three months ago, a coalition led by Saudi Arabia began targeting the rebels with air strikes. Since then, well over 2,000 people have been killed in the conflict, including at least 1,400 civilians, according to the UN.